Toyota Repair/Scraping & howling noise from rear wheels

I have a 4th generation 2003 Toyota 4Runner (4.7L V8 DOHC 32V / Sport Utility 4-DR / 4 Wheel Dr.) with about 90K miles on it.
I'm hearing a scraping noise from the left rear wheel at low speed, and a howling noise from it at highway speed. The scraping noise speeds up as the SUV speeds up. I also hear a scraping (like metal on metal) noise from the right rear wheel when turning.

I changed the rear brakes about 2 years ago & they still have a decent amount of material on them and function fine when I use them. I also checked that the dust shields are not bent and contacting the rotors. I don't see any shiny metal wear marks on either side. I also lifted the rear and spun the wheels by hand to check for excessive brake drag on the wheels, but didn't observe any problems. The tire treads are still within specs, and are not unevenly worn. I have rotated them regularly (front to back). The shocks are OK as well.

I am suspecting the bearings but I am not sure.
I tested each wheel by trying to move them back & forth with the vehicle jacked up, but did't notice any looseness (3 & 9 o'clock, as well as 12 & 6 o'clock).
If it is the bearings, could you tell me how involved the repair would be for the rear wheels (i.e. press required, special tools needed...) Do you have any suggestions on other things I should check?

Thanks.

AnswerHello, it sounds like the bearing is the problem, replacing it requires removal of the axle, a press is required to get the gearing off the axle shaft and to put a new bearing on, not really a DIY job unless you remove the axle yourself, buy the bearing and the ABS ring (if it has ABS) and have a shop install it for you, a new axle seal would also need to be insatalled, you will save some labor costs that way.

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Thanks for your advice Ted, I will have to take it to a shop & have the work done.

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